Adaptive active clearance control logic

Abstract

Systems and methods for adjusting blade tip clearance targets and utilizing the adjusted targets to optimize the clearances between the blade tips and surrounding shrouds of a turbine engine are provided. In one exemplary aspect, one or more engine controllers utilize a machine-learned model to customize blade tip clearance targets based on the way an engine has been uniquely operated in the past for a particular flight mission. Present flight data associated with a present flight of a given flight mission is obtained. A model blade tip clearance target is adjusted based at least in part on the machine-learned model and the present flight data. The machine-learned model is trained at least in part on past flight data indicative of the manner in which the turbine engine has been operated for one or more past flights of the flight mission. An adjusted blade tip clearance target is then generated.

What is claimed is: 
     
       1. A method for optimizing blade tip clearances of a turbine engine mounted to or integral with an aircraft for a flight mission, the method comprising:
 obtaining, by one or more engine controllers, present flight data associated with a present flight of the flight mission; 
 adjusting, by the one or more engine controllers, a model blade tip clearance target based at least in part on a machine-learned model and the present flight data, wherein the machine-learned model is trained at least in part on past flight data indicative of the manner in which the turbine engine has been operated for one or more past flights of the flight mission, wherein the past flight data includes one or more past flight profiles indicative of one or more transition periods in which the aircraft is expected to perform an expected maneuver; 
 generating, by the one or more engine controllers, an adjusted blade tip clearance target; and 
 in response to whether the adjusted blade tip clearance target is adjusted to a predetermined target setting prior to entering one of the one or more transition periods, adjusting, by the one or more controllers, the adjusted blade tip clearance target back to the model blade tip clearance target during the transition period. 
 
     
     
       2. The method of  claim 1 , wherein during obtaining, the present flight data includes one or more waypoints indicative of the flight mission for the present flight. 
     
     
       3. The method of  claim 1 , wherein the past flight data includes one or more past flight profiles indicative of a time at phase for the one or more past flights flown for the flight mission. 
     
     
       4. The method of  claim 3 , wherein the one or more past flight profiles are indicative of one or more cruise phases for the one or more past flights flown for the flight mission, and wherein when the aircraft is operating in the one or more cruise phases, the blade tip clearance target is adjusted to a predetermined target setting. 
     
     
       5. The method of  claim 4 , wherein the predetermined target setting is a minimum clearance setting. 
     
     
       6. The method of  claim 4 , wherein the predetermined target setting is set within a margin of a minimum clearance setting. 
     
     
       7. The method of  claim 6 , wherein the method further comprises:
 generating, by the one or more engine controllers, a confidence score associated with the adjusted blade tip clearance; and 
 adjusting, by the one or more engine controllers, the margin based at least in part on the confidence score associated with the adjusted blade tip clearance. 
 
     
     
       8. The method of  claim 4 , wherein the predetermined target setting is set within a margin of a minimum clearance setting, wherein the margin is within at least twenty-five percent of the minimum clearance setting. 
     
     
       9. The method of  claim 1 , wherein the past flight data includes one or more past operating parameters indicative of the manner in which the turbine engine has been operated for the one or more past flights of the flight mission. 
     
     
       10. The method of  claim 9 , wherein the one or more past operating parameters includes a core speed. 
     
     
       11. The method of  claim 9 , wherein the one or more past operating parameters include at least one of an aircraft gross weight and a fuel load of the aircraft. 
     
     
       12. The method of  claim 1 , wherein after the transition period, if the aircraft subsequently enters a cruise phase, the method further comprises:
 adjusting, by the one or more controllers, the model blade tip clearance target back to the adjusted blade tip clearance target at a predetermined target setting during the cruise phase. 
 
     
     
       13. The method of  claim 1 , wherein the aircraft includes a flight management system communicatively coupled with the one or more engine controllers, and wherein the past flight data includes at least one or more past flight conditions and past flight management system data indicative of flight conditions and communications obtained from the flight management system for the one or more past flights flown for the flight mission. 
     
     
       14. The method of  claim 1 , wherein the machine-learned model is a machine or statistical learning model structured as one of a linear discriminant analysis model, a partial least squares discriminant analysis model, a support vector machine model, a random tree model, a logistic regression model, a nave Bayes model, a K-nearest neighbor model, a quadratic discriminant analysis model, an anomaly detection model, a boosted and bagged decision tree model, an artificial neural network model, a C4.5 model and a k-means model. 
     
     
       15. The method of  claim 1 , wherein the present flight data associated with a present flight for the flight mission includes one or more present operating parameters indicative of the manner in which at least one of the turbine engine and the aircraft is presently being operated for the present flight of the flight mission. 
     
     
       16. The method of  claim 1 , wherein the past flight data includes one or more past flight profiles each indicative of a transition period in which an expected maneuver is expected to be performed. 
     
     
       17. A method for adjusting blade tip clearances between a rotor blade tip and a shroud of a turbine engine for a flight mission, the method comprising:
 comparing, by one or more engine controllers, an instantaneous blade tip clearance to an adjusted blade tip clearance target, wherein the adjusted blade tip clearance target is generated at least in part on a machine-learned model, present flight data, and within a margin of a minimum clearance setting set based at least in part on a confidence score generated by the one or more controllers, the present flight data being associated with a present flight of the flight mission; and 
 aligning, by the one or more engine controllers, the instantaneous blade tip clearance with the adjusted blade tip clearance target; 
 wherein the machine-learned model is trained at least in part on past flight data indicative of the manner in which the turbine engine has been operated for one or more past flights of the flight mission. 
 
     
     
       18. The method of  claim 17 , wherein the past flight data includes one or more past flight profiles indicative of a time at phase for the one or more past flights flown for the flight mission. 
     
     
       19. A system for adjusting blade tip clearances of a turbine engine during operation of a present flight of a flight mission, the system comprising:
 one or more engine controllers comprising one or more processors and one or more memory devices, the one or more memory devices storing instructions that when executed by the one or more processors cause the one or more processors to perform operations, the one or more engine controllers configured to:
 obtain present flight data associated with the present flight of the flight mission, the present flight data indicative of one or more waypoints of the present flight; 
 adjust a model blade tip clearance target based at least in part on a machine-learned model the present flight data, and within a margin of a minimum clearance setting set based at least in part on a confidence score generated by the one or more controllers; 
 generate an adjusted blade tip clearance target indicative at least in part on the manner in which the turbine engine has been actually operated for one or more past flights of the flight mission; 
 compare an instantaneous blade tip clearance to the adjusted blade tip clearance target, and 
 align the instantaneous blade tip clearance with the adjusted blade tip clearance target. 
 
 
     
     
       20. The system of  claim 19 , wherein the machine-learned model is trained at least in part on past flight data that includes one or more past operating parameters indicative of the manner in which the turbine engine has been operated for the one or more past flights of the flight mission, and wherein the one or more past operating parameters include at least one of an aircraft gross weight and a fuel load of the aircraft.